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Assuming two possible gender outcomes among newborn baby whales (male/female), and also assuming a 50-50 probability of male or female, answer the following questions. How many possible male/female outcomes are possible among 2 randomly selected baby whales? [outcomes] What is the probability of finding only 1 female among the 2 randomly selected baby whales? (round to 2 decimal places and report as a number, not a percent) [probf] Hint: Use the Fundamental Counting Rule to find the total possible outcomes, and the Combination rule to find how many ways to get exactly a certain number of outcomes from among the larger group. Finally, divide the latter from the former to find the probability.

Identify the following variable as being either continuous or discrete. The average time students in STAT2040 spend studying for Exam 3.

A customer service center receives an average of 50 complaints per day, with a standard deviation of 12. Based on this information, and for a randomly selected day, answer the following questions. Round all probabilities to 3 decimal places: What is the probability of receiving less than 30 complaints? [p1] What is the probability of receiving more than 58 complaints? [p2] Would it be unusual to receive more than 58 complaints? (yes or no) [yesno] What is the probability of receiving between 40 and 60 complaints? [p3]

Find the mean and standard deviation for a binomial distribution with n = 44 and p = 0.36. Mean = [mean] Standard Deviation = [stdev] (Note: answer in decimal form, rounding the mean to 1 decimal place, and the standard deviation to 2 decimal places)

Use the following data of monthly visits to a popular national park to complete the Pareto table shown. Although not required for this quiz, you should be able to construct a Pareto Chart of this data (please practice). JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC 100,020 106,258 146,876 228,212 326,017 449,566 531,864 508,094 393,437 272,200 121,622 96,745 116,984 111,506 137,550 174,337 280,335 445,887 536,683 604,093 405,605 316,366 136,390 112,928 108,906 113,695 141,766 186,682 295,511 436,862 513,789 570,914 426,684 300,919 149,828 116,311 102,455 101,897 142,141 192,936 315,897 434,014 528,849 591,196 448,519 264,465 137,876 108,486 93,633 103,444 136,523 216,087 317,009 454,638 548,440 546,981 388,707 324,484 144,958 125,999 Bin Frequency 200000 26 600000 9 400000 [f3] 500000 [f4] 300000 6 100000 2 700000 1 More 0  

Data indicates that 48% of voters favor a certain ballot measure. For groups of 45 voters, find the variance. Hint: the distribution is binomial. Variance = [variance] Note: answer in decimal form and round to 2 decimal places

If z is a standard normal variable (normally distributed), find the probability that z lies between 0.70 and 1.98. Probability = [probability] Note: answer in decimal form and round to 3 decimal places.

The number of calls received by a towing service follows a Poisson distribution, with an average of 21.6 calls per day (24 hour period). Find the probability that in any randomly selected hour the number of calls is 1. (hint: start by finding the average calls per hour). Note: enter your answer in decimal form and round to 3 decimal places.

For the following data, compute the z-score and note whether or not it is “unusual.” Round all z-scores to 2 decimal places. Answer “yes” if unusual, or “no” if not unusual (no quote marks). Answers must be exact and precise. Remember that z-scores represent how many standard deviations a value is from the mean, and any value more than 2 standard deviations either below or above from the mean is considered “unusual”. value mean std dev 140 120 15 z-score [zscore] (round to 2 decimals) Unusual? [unusual] (yes or no)

Given the following data, answer the following questions. Hint: Start by putting the data in a Contingency Table. In a study of smokers and non-smokers, the following data was obtained. Among 100 randomly selected 18-22 yr olds, 30 smoke and 70 do not. Among 110 randomly selected 23-30 yr olds, 25 smoke and 85 do not, and among 120 31-40 yr olds, 20 smoke and 100 do not. What is the probability of randomly picking someone from the study who is 31-40 yrs old and smokes? [31andsmoke] What is the probability of randomly picking someone from the study who is 18-22 yrs old or is a non-smoker? [18orNS] What is the probability of randomly picking someone from the study who smokes, given they are 23-30 yrs old? [Sgiven23] note: answer in decimal form and round to 3 decimal places